Specify root namespace for fftw_plan from FFTW3 library. After changeset de091f956edd (the ei_ --> internal:: change), there are two symbols called fftw_plan, one from the FFTW3 library and one from Eigen.
Specify root namespace for fftw_plan from FFTW3 library.
After changeset de091f956edd (the ei_ --> internal:: change), there are two symbols
called fftw_plan, one from the FFTW3 library and one from Eigen.

pthulhu/eigen,pthulhu/eigen,cjntaylor/eigen,cjntaylor/eigen,pthulhu/eigen,cjntaylor/eigen,pthulhu/eigen,pthulhu/eigen,cjntaylor/eigen